The major goal s of the Multipurpose Arthritis and Musculoskeletal Disease Center (MAMDC) at UCSF are: (i) to conduct research regarding the epidemiology of arthritis and musculoskeletal disease (A&MDs), the factors affecting the outcome of A&MDs, and the health care of people with A&MDs; (ii) to conduct basic research in ares related to the etiology and pathogenesis of A&MDs; (iii) to develop and evaluate new methods for the diagnosis, prevention, and treatment of A&MDs; (iv) to train biomedical scientists, physicians, and other health professionals whose work bears on the problems of people with A&MDs; (v) to provide education programs in the field of A&MDs; and (vi) to work with local, state and national organizations to advance knowledge of A&MDs and to promote care of patients with these diseases. To meet these objectives, comprehensive programs have been developed at the three major teaching hospitals at UCSF: Moffitt-Long, the VA Medical Center, and the San Francisco General Hospital. The Center has functioned in a manner that utilizes each of these sites and, by fostering interaction among them, has developed programs that could not have succeeded at a single institution. The Education, Epidemiology, and Health Service Research (EEHSR) Component has developed a strong program that has traditionally focused on health services research. With this renewal, the EEHSR component expands its recent work in genetic epidemiology and extends its scope to include health psychology and pediatric rheumatology. In this way, the expertise within the EEHSR component will link directly the EEHSR and biomedical research components of our center (through the genetic epidemiology project), and will extend the impact of the UCSF MAMDC to new areas, particularly pediatrics. Three major projects are proposed, along with two Development and Feasibility Studies (D&F) studies that are designed to foster the development of the health psychology and pediatrics initiatives. The EEHSR component also includes a Core Unit for the collection, maintenance, and analysis of data that serves several projects. The Biomedical Research Component of the MAMDC at UCSF encompasses a broad range of basic research activities that are well funded from other sources. This has provided fertile ground for the success of D&F studies and for the training of young investigators. Five D&F studies comprise this component. Pediatric rheumatology is represented among these proposals as part of our plan to create a substantive role for pediatrics within our MAMDC. The other D&F studies address diverse topics, including autoimmunity and tolerance, crystal-induced arthritis, and osteoporosis.